Put the mushrooms in a large bowl of cold water to soak for 10 minute Rinse them well and then drain.
Heat a large sauté pan with a tight-fitting lid over medium heat. Add the drained mushrooms to the dry pan, cover immediately, and cook until all the moisture from the mushrooms is leached out, about 20 minute You'll know this has happened when you lift the lid for a peek and see the once-dry pan filled with liquid.
Remove the lid, raise the heat to medium high, and boil until the liquid evaporates and the mushrooms begin to sizzle in the dry pan but haven't browned; they'll have shrunk considerably and should be firm when poked with a fork. Lower the heat to medium and stir in 1 Tbs. of the olive oil, the parsley, and the garlic. Sauté, stirring frequently, until the garlic softens, another 3 to 4 minute Transfer the mushrooms to a serving bowl, stir in the remaining 3 Tbs. olive oil, and season with salt to taste (I like to salt them liberally). Serve while hot.